Clamshell



raras JOSEPH MARTIN, OF MUNICH, GERMANY.

CLAMSHELL.

Application filed August 29, 1921.

Serial No. 496,739.

(GEAETED UNDER THE PROVISIONS or 'rnE .ier or Manen 192i, 41 straat., 1313.)

To all 'whom imag concern:

Be it known that I, JOSEPH MARTIN, a citizen of the German Republic, residing at 40 Bauerstrasse, Munich, Bavaria, Germany, have invented certain new and useful Improvements in Clamshells (for which I have filed applications and obtained patents as follows: Germany, patents led (a) 26 Feb., 1919, date of grant, 1 Nov., 1921, No. 846,- 966, (b) 6 Feb., 1919, date of grant, 15 July, 1921, No. 841,662; ltaly, patent led 30 J une, 1920, application No. 291/268, still pending; Austria, patent filed 1 July, 1920, date of grant, 28 Apr., 1922, No. 89,494; Great Britain, patent filed 2 July, 1920, date of grant, 3 Oct., 1921, No. 169,791; Belgium, patent led 5 July, 1920, date of grant, 14 Aug., 1920, No. 288,681; France, patent filed,

10 July, 1920, date of grant, 12 Feb., 1921,

No. 520,861; Sweden, patent filed 12 July, 1920, application No. 8962/20, still pending; Netherlands, patent led 11 Aug., 1920, date of grant, 2 June, 1922, No. 7 955; Hungary, patents filed (a) 21 Aug., 1920, date of grant, 4 Oct., 1921, No. 80,468, (b) 21 Aug., 1920, application No. M6881, still pending; Czechoslovakia, patent filed 27 Nov., 1920, application No. P9108-20, still pending), of which the following is a specification.

My invention relates to improvements in clam-shells for handling coal, ore, garbage and the like, and it is one of the essential objects of the invention to provide a clamshell which is readily movable, and in which means are provided which will cause it (without any additional load) to open reliably in consequence of its own weight and the load of its charge, and in which the proportion of its own weight to the weight of the charge is more favorable than heretofore.

A further object of the invention is to dispose the pulley ropes for closing the clamshell in such a manner, that they can not be clogged up by dirt and to provide means,

preventing undue friction or catching at the ropes and rope pulleys, so that the pulleys will at all times remain readily rotatable and the ropes run properly.

These and other objects and advantages of i the invention and Vits design will be fully disclosed in and by the following specification, reference being had to the accompanying drawing, in which Fig. 1 is a front elevation of the closed 55 clam-shell.

Fig. 2 is a side elevation of the clam-shell. i Fig. 8 shows the clam-shell in open position. A

Fig. 4 is the arrangement of the rollers Go for the pulleys on an enlarged scale, shown partly in section. y

In constructing the clam-shell 1 attach a pair of shells a at the ends of long leverarms b, which, at their other ends are pivoted to a common shaft c. At both sides of the clam-shell l provide in the lower half of the shells, pulleys 7', over which ropes Z are running for closing the clamshell. At the highest point of the clam-shell, close to the shaft c guide pulleys e are provided, over which the closing ropes d are running in such a manner, that they leave the clam-shell in the plane of its center of gravity. The clam-shell is secured by means of pairs of chains or ropes a'- of constant length to a bridge located above it. this bridge it being coupled by a rope g to a crane, winch or the like. The said pairs of ropes i are attached at the points, where the shells a have their maximum width. The width of the bridge h is greater than that of both shells together, so that, when the clam-shell is closed (Fig. l) the pairs of carrier ropes z' diverge upwardly. Thereby 85 I obtain, that, when the clam-shell begins to open, horizontally extending and outwardly directed opening components will act upon the shell halves. The opening of the clam-shell is effected in the following manner: The bridge hy is held by its rope g, and the closing ropes d are slackened. rlhereby turning movements are produced, the axes of which lie partly in the ends of the bridge 7L., partly in the points where the ropes z' act 95 on the shell halves. With the hereinbefore described arrangementthe maximum opening moments appear with regard to these points. For the purpose of preventing the pulleys f which are fitted to the outside of the shells, to be clogged by dirt, they are covered with hoods 7c. As, nevertheless, the ropes CZ may drag grit or dirt beneath the hoods 7c, which could stick to the grooves of the pulleys and cause the ropes d to catch in the hoods 7a, the bottom of the grooves in the pulleys is made, as shown in Fig. 4, flat instead of conical as heretofore, and besides much VWider than the ropes d. I obtain thereby that the ropes can slip on the bottom of the grooves axiallyto the pulleys, so that they will push aside any particles of dirt dragged into the pulleys, and these will fall off, or, on the other hand, the ropes can be i'orced aside, to clear the dirt. A further improvement in this direction I obtain by perforating the bottom of the grooves j' With y 2. comparatively light with regard to its capacity, and which 3. will Vclose easily, and

ll-. will open reliably and quickly at the most favorable utilization of its own Weight and the load of the charge.

Having thus described my invention What I claim as newA and desire to secure by Letters Patent is: Y

1. In a `cla-m shell iny combination a pair of shells attached to long shell levers pivotedto one another at their extreme ends, a bridge piece above the shells and suspension members of invariable length Vbet-Ween the ends of said bridge and the outermost points of the shells, said bridge being of greater length than the distance, between the outermost points of the shells in the closed position of the latter.

2. In a clam shell in combination a pair of shells lrigidly attached to long shell .levers pivoted to one anotherat their eXtreme ends, a suspension bridge for the shells, and fleX- ible suspension members ofinvariable length between the ends. of said' bridge'` and the. outermost points ofthe shells diveroing upwardly in the closed position of the clam shell. Y

In testimony whereof I aix my signature.

JOSEPH 'MARTIN 

